958 SCIENCE. 
trials this author draws far-reaching 
conclusions and even ascribes all actions of 
living protoplasm to the presence of an ex- 
ceedingly small quanity of ‘bionuclein,’ 
present in albuminous matters of the 
cells. 
The writer in 1882 proposed the view 
that enzymes are like the protein bodies of 
the living protoplasm distinguished by the 
presence of chemically labile atomic groups * 
and said at that time: “it seems as if 
some remnant of the active powers of the 
protoplasm must be contained in the 
enzymes.’’ Later on, somebody else called 
enzymes ‘protoplasm splinters’ and since 
then this phrase has been echoed by many 
who did not conceive or concede that the 
principle common to both consisted in chem- 
ical lability. 
The principle of chemical lability (insta- 
bility) has thus far been but little studied. 
The writer has recently suggested the desira- 
bility of distinguishing between kinetically- 
labile and potentially-labile compounds.; A 
kinetically labile compound is characterized 
on the one hand, by the easy change to a 
more stable, isomeric or polymeric modifi- 
cation or compound, and on the other, by 
the great facility with which it enters into 
reactions with various other compounds, 
especially with such as also possess labile 
properties, whereby result products with a 
less degree of instability. Potentially labile 
compounds behave differently, they do 
not pass into isomeric or polymeric modi- 
fications, do not easily yield various 
derivatives, but are inclined to sudden 
far-reaching decomposition or explosion. 
Examples of the former class are aldehydes, 
* Pfliiger’s, Archiv, Vol. 27, p. 211. Also, Journal 
fiir praktische Chemie, Vol. 37, p. 103. 
+A detailed account of this view, explained by 
numerous examples is contained in Chapter 11, of 
the treatise of the writer: ‘‘ Der chemische Energie 
der Jebenden Zellen,’’ recently published in Munich 
by Dr. E. Wolff. 
[N. S. Vou. X. No. 261. 
amido-aldehydes, amido-ketones; of the lat- 
ter class, the diazo-compounds and the ni- 
trates of polyvalent alcohols as nitroglyce- 
rol. Kinetic lability comprises free chemical 
energy while potential lability intra-molec- 
ular chemical energy of position to be well 
distinguished from the potential energy rela- 
tively to oxygen, a potential energy present 
in all organic compounds and liberated in - 
the act of combining with oxygen. 
Chemical energy consists in certain 
motions of atoms, motions of larger ampli- 
tudes than the motions of heat energy, al- 
though easily passing into the latter. We 
must infer the larger amplitudes of chem- 
ical energy from the fact that at the ordi- 
nary temperature the chemical energy can 
counteract the force of affinity in a much 
larger measure than heat energy can do. 
it. 
Free chemical energy in a labile com- 
pound is caused by a loose position of atoms. 
in certain atomic groups, and this loose 
position is the consequence of a depression 
of affinities on account of one atom being 
under the simultaneous influence of two. 
neighboring atoms. Such atoms in loose 
position are subjected to much more vio-. 
lent oscillations under the influence of heat. 
energy than are the other atoms in stable 
position in the same compound. Thus, heat 
energy is easily transformed into chemical 
energy by labile atomic groups. As the 
writer first pointed out, such machines to 
transform heat into chemical action are, the 
proteins of the living protoplasm and also the 
enzymes, the latter, however, in a much less 
degree than. the former. 
The organized proteins of the living mat- 
ter produce their own heat by respiration, 
whilst the enzymes utilize either the free 
store of heat energy in the atmosphere 
when they act at the ordinary temperature, 
or also the heat of other sources when they 
act at an elevated temperature. 
Let us now review the general chemical 
